<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <link rel="stylesheet" href="./demo.css">

</head>

<body>
  <!-- Tab选项卡1 -->
  <div class="box tab1">
    <!-- 标题 -->
    <ul>
      <li class="active">1</li>
      <li>2</li>
      <li>3</li>
    </ul>
    <!-- 内容 -->
    <ol>
      <li class="active">1</li>
      <li>2</li>
      <li>3</li>
    </ol>
  </div>
  <!-- Tab选项卡2 -->
  <div class="box tab2">
    <!-- 标题 -->
    <ul>
      <li class="active">1</li>
      <li>2</li>
      <li>3</li>
    </ul>
    <!-- 内容 -->
    <ol>
      <li class="active">1</li>
      <li>2</li>
      <li>3</li>
    </ol>
  </div>
   <!-- Tab选项卡3 -->
   <div class="box tab3">
    <!-- 标题 -->
    <ul>
      <li class="active">1</li>
      <li>2</li>
      <li>3</li>
    </ul>
    <!-- 内容 -->
    <ol>
      <li class="active">1</li>
      <li>2</li>
      <li>3</li>
    </ol>
  </div>
  <script src="./demo.js"></script>
  <script>
    let obj1 = new Tab('.tab1')
    let obj2 = new Tab('.tab2')
    let obj3 = new Tab('.tab3')
  </script>
</body>

</html>